This commit expands tabs to spaces (ts=4) in all the files under src/
and test/.
Until now we had two wildly different code styles with C using tabs and
new C++ using spaces. It is painful to maintain as none of the commonly
used tools support this kind of setup and in reality is needless, as we
can simply convert all the sources to spaces and have opened PRs do the
same, where needed.
Additionally, trailing whitespace has been removed.
This way the last remaining uses of int could be replaced with sint32 as
well. Before this change there was a circular dependancy which made the
types unknown in diagnostic.h.